tools: update doc dependency mdast-util-gfm-table to 1.0.2

This fixes a bug that causes our tooling to generate invalid HTML. (The
`align` attribute on `tr` and `td` elements was ending up with the
invalid value of `"none"`.)

Refs: remarkjs/remark-gfm#29
Refs: syntax-tree/mdast-util-gfm-table@a28b860

PR-URL: nodejs#41260
Reviewed-By: Michaël Zasso <[email protected]>
Reviewed-By: Colin Ihrig <[email protected]>
Reviewed-By: James M Snell <[email protected]>
Reviewed-By: Luigi Pinca <[email protected]>

Author: Trott